Banana-based Plastics For Cars – Science Explained

Here’s a crazy news item – CNN.com reported that fruit skins have been used to inspire new plastic designs. According to the report:

Scientists in Brazil say they’ve developed a way to use fibers from the fruits to make strong, lightweight plastics that could be used to form car parts…the leader of the project, Alcides Leão of Sao Paulo State University, said “They are light, but very strong — 30 per cent lighter and three to four times stronger. We believe that a lot of car parts, including dashboards, bumpers, side panels, will be made of nano-sized fruit fibers in the future…they will help reduce the weight of cars and that will improve fuel economy.”

There are a lot of words tossed out – nano-sized fruit fibers being one of the more interesting. Here’s what it means:

What’s a Nano-Sized Fruit Fiber?

It’s science nerd for “very small plastic molecules derived from biologic mass” – another industry term would be a “bio based nano-polymer.”

In this example, the biological base is fruit fibers, specifically the tough skins on fruits like bananas, coconut shells, agave (the mother plant of tequila), etc. These fruits all have one thing in common – tough cellulose structures. By copying the natural design of these skins, plastics can be made stronger.

While this is definitely interesting technology, the fact is that bio-based plastics aren’t very new. Toyota first used a bio-based plastic in a car in the early 90’s, and since the middle of the last decade Toyota (along with Honda and Hyundai) have been using fairly significant amounts of bio-based plastic in their vehicles (Toyota has consistently been the leader in the industry in bio-plastics according to EcoCenter.org).

What makes these new plastics exciting is that they’re using nano-technology AND a biological base. Think of it as reverse engineering the toughness of a banana peel, then multiplying the strength, and then figuring out how to make it 100 times smaller…or something like that.

The alternative to bio-based plastics are petroleum based plastics, but they’re less desirable because they can:

• give off toxic gases (new car smell is a combination of these plastics letting out compounds)
• fluctuate in price because of the oil market
• sit in landfills for eons

Bio based plastics are good for the Earth and probably healthier for us too.

Bottom Line: Plastic parts are going to get thinner and lighter going forward, but they’re also going to get stronger. We’ll start seeing these plastics used on interior parts in the short term, but in the long term we’ll see them used on exterior parts too. This is one of the many ways automakers will reduce weight to prepare for the new fuel economy rules.